I also tend to focus on the end game for cryptocurrency: being a better form of money. While the ascend to adoption is a great ride, the core application of Bitcoin (to me) is being an honest ledger. A true and verified account of what happened. In the end, that should lead (if Bitcoin becomes the one to lead them all) to better coordination among people from an economic perspective, and thus more wealth for us all.
That (to me) is the big promise of Bitcoin.
For some food for thought on Bitcoin serving as a stable numeraire, see: http://www.gata.org/node/8303 (Bitcoin not mentioned as option since the piece is form 2001)